Waterproofing was a major concern, particularly for the archive. "It's a product that ages, things like caulking of joints and sealing of walls. So the systems that we put in place were far more extensive than [normal]. It took quite a bit of work with the trade contractors to take the details that [the architect] Stern wanted, which was basically invisible. They didn't want to see any connections, so you have the aspect of trying to make it very architecturally pleasing while still creating a very robust waterproofing barrier to keep the building dry," Penny says.

"Close coordination with the design team allowed us to integrate these systems and maintain the aesthetics the architect required," Proehl adds.

Each face of the building has its own unique aspects as well. To the south, for example, the institute faces a 15-acre urban park featuring such native landscaping as a wildflower meadow, a tall grass prairie and savannah, and woodland clearings.

The expansive landscaping on the property added its own challenges because the owner wanted to have a year's worth of growth on the landscaping so it would be robust in time for opening day—a difficult task since landscaping is typically the very last thing done on a project, Penny says. So "we were trying to put the landscaping in before the building was done," he says.

More than 1,000 trees were planted, and finely engineered soils were used to create sustainable features.

The Bush Center is only the second museum-type building in the country to achieve LEED-Platinum certification, Arendt says.

"That's because of the unique characteristics of museums and the energy requirements that they have," he says. "It was very carefully planned and executed."

Penny notes that the project was more challenging than a typical LEED-Platinum job because of the security and archive requirements.

The project team utilized green-building materials and energy-efficient technologies. Sustainable design elements include regional and recycled building materials, highly efficient HVAC systems, photovoltaic and solar hot water panels, low-VOC-emitting products, mechanical air filtration and green roofs.

"We've also got sustainable landscaping, with a 250,000-gallon cistern collecting rainwater runoff, plus condenser water runoff from the air-conditioning unit, used to irrigate landscaping when needed," Penny says.

In the end, Manhattan and its team of subcontractors produced significant savings for the owner.